Sensitizing agents comprising the reaction product of urea-formaldehyde-hydrogen peroxide



Uflitfid stattistpflttiflt o lcfi SENSITIZING AGENTS COMPRISING THE- RE- ACTION PRODUCT OF UREA-FORMALDEHYDE- HYDRGGEN PEROXIDE i Luther 0. Young, Baltimore, Md., assignor to R.

Grace & C0,, a corporation of Connecticut No Drawing. Filed Mar. .22, 1963, Ser. No. 267,321

Claims. (Cl. 149-46) The present invention relates to improvements in explosives, and more specifically to improvements in chemical explosive compounds. I

Explosives have become increasingly important articles of commerce. Civilian use extends to coal mining, metal mining, quarrying and. non -metal mining, railway and other construction. While the military uses extend .from small arms ammunition and high explosive shells to rocket propellants.

These varied uses require difierent kinds of explosives,

ranging from the very low pressure explosives such as propellants, to the highest pressure military explosives. Between these two extremes, there exists an almost continuous distribution of conditions requiring explosives of all sorts of pressure and rate characteristics. Considerable interest has developed in the area of sensitizing compounds for relatively insensitive explosives. There are many requirements which must, be met by a Prior art sensitizing materials. sometimes fall It is" therefore an object of the present invention to pror explosives thereby rendering themmore useful. r r r j It is another object to provide a chemical senslitizerfor explosives which is inexpensive,- c'ompatible with-fox- -vide an improved chemicals'ensitizing age tror insensitive plosives and liberates a. high volume;of gas perunit Q weight. r Q K These and furtherobjects of. thepresent invention will become readily apparent from the scription andspecificexamples. Broadly, the present invention contemplates the use or;

following detailed deij 3,l66,451 I Patented Jan, 19,1965

(trinitrot ol uene, trimethylerietrinitramine), PETN (pentaerlythritol tetranitrate), ammonium picrate, ,pieric acid, ammonium nitrate, DNT (dinitrotoluene) EDNA- (ethylenediaminedinitrate), NG .(nitroglyceriuLAN (ammonir um nitrate, nitrostarch), and the like; low explosives such as smokeless powder, nitro-cotton, NG (nitroglycerine), black powder (potassium nitrate, sulfur, charcoal), DNT (dinitrotoluene) and the like. -The preferred explosives are sodium nitrate, ammonium perchlorate, ammonium nitrate, TNT, and DNT.

UFP is also compatible and may be admixed with nonexplosive ingredients commonly found with explosives such. as aluminum, waxes, diphenylamine, metal nitrates, mononitrotoluene, ferrosilicon, wood pulps, meals, andother combustibles, paraffin, and other hydrocarbons, chalk, sulphur, carbon and the like. u The method of detonating mixtures of UFP and ex: plosives, obviously dependsupon the particular mixture. When the UFPis mixed with a primary high explosive,

the explosive isinitiated bysimple ignition, by such means 7 u as spark, flame, impact, and other-primary sources of heat. For mixtures of- UFP and'secondary explosives,

(the most practical manner of --initiating an explosive is Preparation of UFP (urea-formaldehyde-hydrogen peroxide) a r A gallon stainless steel ma; provided with agrarian and a portable cooling unit was used as the reaction vessel.

The followingwereprecooled and placed in the-.tank:' 56.4 153. of 35% forr'iialdehydesolution,UFP;

79.1 lbs. of 37% hydrogen peroxide solution,'C.I.; i i

The mixture was stirred until the urea was completely dissolved and cooled until the temperature reached 5 C.

Concentrated nitric acid (reagent grade) was slowly added j to the mixturewithstirring. After- 5 pintsof acid were 7 i added, reaction aand precipitation began. After the addi-J a urea-formaldehyde-hydrogen3'peroxide reaction product.

(herein designated UFP).-as 'acsensitizing agent f0r.ex-

plosives. ThisUFP product is known' to the art. While the precise chemical stnlcturefof the, UFP product is not knovm it possesses the empirical formula C H N Q and may be readily prepared by reacting urea, formaldehyde and hydrogen peroxide in the presence of concentratedfl (-71%) nitric acid; The product is. aflwhite crystalline compound which meltswith decomposition at 200, C. and is obtained in good yield using the method described above. Thisproduct is described in the literatureby r Griswald and Siegens in Berichte 47, pages 2464-9 and also in Berichte 54B, pages 4928 (1921). r

UFP. is relatively insensitive t9 impact. However,'I

have foundthat if from about 5 percentto about per- Explosives with] which the present compounds 7 may be effectively blended are:

Primary high explosives, such as mercury'fulminate,

, lead azide, diazodinitrophenol, lead styphnate, nitrornannite and the like; secondary high explosives, such as TNT plosives drop test apparatus, using a two i weight and a 10 milligram sample.

determined on the a Thetable also shows tionof 38 pints of acid',:the temperature was 28 C. After thisacid addition the mixturewas stirred for 2 hours, and then'diluted 50% withWater. 'Ihe'rnixture was-allowed to stand for 48 hours, then filteredeand washedfree of aci r L EXAMPLE II Drop test for explosive sensitivity l This test was conducted using the Bureau of Ex- All mixtures were oxygen balanced, that is, sufficient oxygenwas present to convert carbon and'hydrogen present to CO 311(11120 respectively. Each-test value was 3 basis of a minimum vof '20 individual tests.

In these sensitivity testsPETN was usedas a comparison asno other commonly used secondary explosive is V more sensitive. r

In Table I are the results of mixtures of UFP and AP (ammonium perchlorate). These mixtures of UFP-AP and aluminum are similar to composite propellants. The results shown that' UFP andammonium perchlorate react readily.

monium perchlorate are more sensitive than mixtures of ammonium perchlorate and other organic materials. An

unobvious result was that UFP influenced sensitivity more than DNT (dinitrotoluene), an explosive itself.

kilogram drop 1 that the mixtures of and amy 7 I Mix SENSITIVITY l'OF UFP AND AMMONIUM PERCHLORATE MIXTURES i l V V D etorz aliilitf of :UFP mixes 67 0; 1.1owderedfa1uminum,

" "These iesults siiow irate, and trinitrotoluene v UFPjS superior to" fuel oil, a sensitizer for ammoniuminitrate'. l

I I claim: I

1.! An explosive composition comprising a sensitizing I amount of a'se'nsitizing agent having an empirical formula V C H N O obtained by reacting urea, formaldehyde, and;

hydrogen peroxide. in the presence ofnitric' acid, said sensitizing agent-'melting with decomposition at 200 C., J andan expiosive selected from thegroup consisting of ammonium perchlorate, ammonium 12;, A composition as'described inclaim 1, wherein the 7 amount of the sensitizing agent is from about 5-95 weight percent; and the amount of said Blendsof UFPandiexplosives were tested/or detonated V I u'singiSQ/SO PETN/TNT) boosters. Measurement of the I V explosive is from about 955 weight percent. 7 i I j p 3. An explosive composition comprising a sensitizing amount of a sensitizing agent having an empirical formula C H N O obtained by reacting, urea, formaldehyde, and

hydrogen peroxide in the'presence of nitric acid, said sensitizing agent melting with decomposition at 200 C.,

an explosive selected from the group consisting of ammonium perchiorat'e andtrinitrotoluene, and a powdered metal, said'metal having a particle size of from aboutf25-' 75 microns. I I

' 4. The composition as described infolaini 3, wherein said metal is aluminum. I I

5 A method of sensitizin'g'expiosives which comprisesa adding a sensitizing amount of a sensitizing agent having anempirical formula C H N O ,obtained by reacting furea, formaldehydegand hydrogen peroxide in the presence of nitric aCid,. "S\id sensitizing agent inelting'jwith der compositionat 200 CI, to an explosive selected fI'OHl the group consisting of ammonium. perchlorate; ammon um nitrate, sodium-nitrate an'dtrinitrotoiuene.

' l fiestas-ea; onesb yfl h ii V UNITED s Ar s ATEnTs I CCARLD- Q AR T s; r mqry im r R UBEN sesrism sx gme i nitrate, sodium ni- I 

1. AN EXPLOSIVE COMPOSITION COMPRISING A SENSITIZING AMOUNT OF A SENSITIZING AGENT HAVING AN EMPIRICAL FORMULA C3H6N2O3 OBTAINED BY REACTING UREA, FORMALDEHYDE, AND HYDROGEN PEROXIDE IN THE PRESENCE OF NITRIC ACID, SAID SENSITIZING AGENT MELTING WITH DECOMPOSITION AT 200*C., AND AN EXPLOSIVE SELECTED FROM THE GROUP CONSISTING OF AMMONIUM PERCHLORATE, AMMONIUM NITRATE, SODIUM NITRATE, AND TRINITROTOLUENE. 